<?php
/**
 * Zend Framework, MySQL Adapter
 *
 * @category   Zend
 * @package    Zend_Db
 * @subpackage Adapter
 * @copyright  Jenei Viktor Attila
 * @license   http://www.opensource.org/licenses/lgpl-license.php LGPL
 */

/**
 * @see Zend_Db_Adapter_Abstract
 */
require_once 'Zend/Db/Adapter/Abstract.php';

/**
 * @see Zend_Db_Profiler
 */
require_once 'Zend/Db/Profiler.php';

/**
 * @see Zend_Db_Select
 */
require_once 'Zend/Db/Select.php';

/**
 * @see Zend_Db_Statement_Mysqli
 */
require_once 'Zend/Db/Statement/Mysql.php';


/**
 * @category   Zend
 * @package    Zend_Db
 * @subpackage Adapter
 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Db_Adapter_Php_Mysql extends Zend_Db_Adapter_Abstract {
    /**
     * Keys are UPPERCASE SQL datatypes or the constants
     * Zend_Db::INT_TYPE, Zend_Db::BIGINT_TYPE, or Zend_Db::FLOAT_TYPE.
     *
     * Values are:
     * 0 = 32-bit integer
     * 1 = 64-bit integer
     * 2 = float or decimal
     *
     * @var array Associative array of datatypes to values 0, 1, or 2.
     */
    protected $_numericDataTypes = array(
        Zend_Db::INT_TYPE    => Zend_Db::INT_TYPE,
        Zend_Db::BIGINT_TYPE => Zend_Db::BIGINT_TYPE,
        Zend_Db::FLOAT_TYPE  => Zend_Db::FLOAT_TYPE,
        'INT'                => Zend_Db::INT_TYPE,
        'INTEGER'            => Zend_Db::INT_TYPE,
        'MEDIUMINT'          => Zend_Db::INT_TYPE,
        'SMALLINT'           => Zend_Db::INT_TYPE,
        'TINYINT'            => Zend_Db::INT_TYPE,
        'BIGINT'             => Zend_Db::BIGINT_TYPE,
        'SERIAL'             => Zend_Db::BIGINT_TYPE,
        'DEC'                => Zend_Db::FLOAT_TYPE,
        'DECIMAL'            => Zend_Db::FLOAT_TYPE,
        'DOUBLE'             => Zend_Db::FLOAT_TYPE,
        'DOUBLE PRECISION'   => Zend_Db::FLOAT_TYPE,
        'FIXED'              => Zend_Db::FLOAT_TYPE,
        'FLOAT'              => Zend_Db::FLOAT_TYPE
    );

    /**
     * @var Zend_Db_Statement_Mysqli
     */
    protected $_stmt = null;

    /**
     * Default class name for a DB statement.
     *
     * @var string
     */
    protected $_defaultStmtClass = 'Zend_Db_Statement_Mysql';

    /**
     * Quote a raw string.
     *
     * @param mixed $value Raw string
     *
     * @return string           Quoted string
     */
    protected function _quote( $value ) {
        if ( is_int( $value ) || is_float( $value ) ) {
            return $value;
        }
        $this->_connect();
        return "'" . mysql_real_escape_string( $value, $this->_connection ) . "'";
    }

    /**
     * Returns the symbol the adapter uses for delimiting identifiers.
     *
     * @return string
     */
    public function getQuoteIdentifierSymbol() {
        return "`";
    }

    /**
     * Returns a list of the tables in the database.
     *
     * @return array
     */
    public function listTables() {
        $result = array();
        $sql = 'SHOW TABLES';
        if ( $queryResult = mysql_query( $sql, $this->getConnection() ) ) {
            while ( $row = mysql_fetch_row( $queryResult ) ) {
                $result[] = $row[0];
            }
        } else {
            require_once 'Zend/Db/Adapter/Exception.php';
            throw new Zend_Db_Adapter_Exception( mysql_error( $this->getConnection() ) );
        }
        return $result;
    }

    /**
     * Returns the column descriptions for a table.
     *
     * The return value is an associative array keyed by the column name,
     * as returned by the RDBMS.
     *
     * The value of each array element is an associative array
     * with the following keys:
     *
     * SCHEMA_NAME      => string; name of database or schema
     * TABLE_NAME       => string;
     * COLUMN_NAME      => string; column name
     * COLUMN_POSITION  => number; ordinal position of column in table
     * DATA_TYPE        => string; SQL datatype name of column
     * DEFAULT          => string; default expression of column, null if none
     * NULLABLE         => boolean; true if column can have nulls
     * LENGTH           => number; length of CHAR/VARCHAR
     * SCALE            => number; scale of NUMERIC/DECIMAL
     * PRECISION        => number; precision of NUMERIC/DECIMAL
     * UNSIGNED         => boolean; unsigned property of an integer type
     * PRIMARY          => boolean; true if column is part of the primary key
     * PRIMARY_POSITION => integer; position of column in primary key
     * IDENTITY         => integer; true if column is auto-generated with unique values
     *
     * @param string $tableName
     * @param string $schemaName OPTIONAL
     * @return array
     */
    public function describeTable($tableName, $schemaName = null) {
        /**
         * @todo  use INFORMATION_SCHEMA someday when
         * MySQL's implementation isn't too slow.
         */

        if ( $schemaName ) {
            $sql = 'DESCRIBE ' . $this->quoteIdentifier("$schemaName.$tableName", true);
        } else {
            $sql = 'DESCRIBE ' . $this->quoteIdentifier($tableName, true);
        }

        /**
         * Use mysqli extension API, because DESCRIBE doesn't work
         * well as a prepared statement on MySQL 4.1.
         */
        if ( $queryResult = mysql_query( $sql, $this->getConnection() ) ) {
            while ( $row = mysql_fetch_assoc( $queryResult ) ) {
                $result[] = $row;
            }
        } else {
            require_once 'Zend/Db/Adapter/Exception.php';
            throw new Zend_Db_Adapter_Exception($this->getConnection()->error);
        }

        $desc = array();

        $row_defaults = array(
            'Length'          => null,
            'Scale'           => null,
            'Precision'       => null,
            'Unsigned'        => null,
            'Primary'         => false,
            'PrimaryPosition' => null,
            'Identity'        => false
        );
        $i = 1;
        $p = 1;
        foreach ( $result as $key => $row ) {
            $row = array_merge( $row_defaults, $row );
            if ( preg_match( '/unsigned/', $row['Type'] ) ) {
                $row[ 'Unsigned' ] = true;
            }
            if ( preg_match( '/^((?:var)?char)\((\d+)\)/', $row['Type'], $matches ) ) {
                $row['Type'] = $matches[1];
                $row['Length'] = $matches[2];
            } else if ( preg_match( '/^decimal\((\d+),(\d+)\)/', $row['Type'], $matches ) ) {
                $row['Type'] = 'decimal';
                $row['Precision'] = $matches[1];
                $row['Scale'] = $matches[2];
            } else if ( preg_match( '/^float\((\d+),(\d+)\)/', $row['Type'], $matches ) ) {
                $row['Type'] = 'float';
                $row['Precision'] = $matches[1];
                $row['Scale'] = $matches[2];
            } else if ( preg_match( '/^((?:big|medium|small|tiny)?int)\((\d+)\)/', $row['Type'], $matches ) ) {
                $row['Type'] = $matches[1];
                /**
                 * The optional argument of a MySQL int type is not precision
                 * or length; it is only a hint for display width.
                 */
            }
            if ( strtoupper( $row['Key'] ) == 'PRI' ) {
                $row['Primary'] = true;
                $row['PrimaryPosition'] = $p;
                if ( $row['Extra'] == 'auto_increment' ) {
                    $row['Identity'] = true;
                } else {
                    $row['Identity'] = false;
                }
                ++$p;
            }
            $desc[ $this->foldCase( $row['Field'] ) ] = array(
                'SCHEMA_NAME'      => null,
                'TABLE_NAME'       => $this->foldCase( $tableName ),
                'COLUMN_NAME'      => $this->foldCase( $row['Field'] ),
                'COLUMN_POSITION'  => $i,
                'DATA_TYPE'        => $row['Type'],
                'DEFAULT'          => $row['Default'],
                'NULLABLE'         => (bool) ( $row['Null'] == 'YES' ),
                'LENGTH'           => $row['Length'],
                'SCALE'            => $row['Scale'],
                'PRECISION'        => $row['Precision'],
                'UNSIGNED'         => $row['Unsigned'],
                'PRIMARY'          => $row['Primary'],
                'PRIMARY_POSITION' => $row['PrimaryPosition'],
                'IDENTITY'         => $row['Identity']
            );
            ++$i;
        }
        return $desc;
    }

    /**
     * Creates a connection to the database.
     *
     * @return void
     * @throws Zend_Db_Adapter_Exception
     */
    protected function _connect() {
        if ( $this->_connection ) {
            return;
        }

        if ( !extension_loaded( 'mysql' ) ) {
            /**
             * @see Zend_Db_Adapter_Exception
             */
            require_once 'Zend/Db/Adapter/Exception.php';
            throw new Zend_Db_Adapter_Exception( 'The Mysql extension is required for this adapter but the extension is not loaded' );
        }

        if ( isset($this->_config['port'] ) ) {
            $port = (integer) $this->_config['port'];
        } else {
            $port = null;
        }

        $this->_connection = mysql_connect(
            $this->_config['host'],
            $this->_config['username'],
            $this->_config['password']
        );
        
        @mysql_selectdb( $this->_config['dbname'], $this->_connection );

        $_isConnected = true;
        if ( !$this->_connection ) {  $_isConnected = false; }

        if ( $_isConnected === false ) {

            $this->closeConnection();
            require_once 'Zend/Db/Adapter/Exception.php';
            throw new Zend_Db_Adapter_Exception( mysql_error() );
        }

        if ( !empty( $this->_config['charset'] ) ) {
            mysql_set_charset( $this->_config['charset'] , $this->_connection ); 
        }
    }

    /**
     * Test if a connection is active
     *
     * @return boolean
     */
    public function isConnected() {
        return $this->_isConnected;
    }

    /**
     * Force the connection to close.
     *
     * @return void
     */
    public function closeConnection() {
        if ( $this->isConnected() ) {
            @mysql_close( $this->_connection );
        }
        $this->_connection = null;
        $this->_isConnected = false;
    }

    /**
     * Prepare a statement and return a PDOStatement-like object.
     *
     * @param  string  $sql  SQL query
     * @return Zend_Db_Statement_Mysqli
     */
    public function prepare( $sql ) {
        $this->_connect();
        if ( $this->_stmt ) {
            $this->_stmt->close();
        }
        $stmtClass = $this->_defaultStmtClass;
        if ( !class_exists( $stmtClass ) ) {
            require_once 'Zend/Loader.php';
            Zend_Loader::loadClass( $stmtClass );
        }
        $stmt = new $stmtClass( $this, $sql );
        if ( $stmt === false ) {
            return false;
        }
        $stmt->setFetchMode( $this->_fetchMode );
        $this->_stmt = $stmt;
        return $stmt;
    }

    /**
     * Gets the last ID generated automatically by an IDENTITY/AUTOINCREMENT column.
     *
     * As a convention, on RDBMS brands that support sequences
     * (e.g. Oracle, PostgreSQL, DB2), this method forms the name of a sequence
     * from the arguments and returns the last id generated by that sequence.
     * On RDBMS brands that support IDENTITY/AUTOINCREMENT columns, this method
     * returns the last value generated for such a column, and the table name
     * argument is disregarded.
     *
     * MySQL does not support sequences, so $tableName and $primaryKey are ignored.
     *
     * @param string $tableName   OPTIONAL Name of table.
     * @param string $primaryKey  OPTIONAL Name of primary key column.
     * @return string
     * @todo Return value should be int?
     */
    public function lastInsertId( $tableName = null, $primaryKey = null ) {
        return (string) mysql_insert_id( $this->_connection );
    }

    /**
     * Begin a transaction.
     *
     * @return void
     */
    protected function _beginTransaction() {
        $this->_connect();
        @mysql_query( 'BEGIN;', $this->_connection );
    }

    /**
     * Commit a transaction.
     *
     * @return void
     */
    protected function _commit() {
        $this->_connect();
        @mysql_query( 'COMMIT;', $this->_connection );
    }

    /**
     * Roll-back a transaction.
     *
     * @return void
     */
    protected function _rollBack() {
    	$this->_connect();
        @mysql_query( 'ROLLBACK;', $this->_connection );
    }

    /**
     * Set the fetch mode.
     *
     * @param int $mode
     * @return void
     * @throws Zend_Db_Adapter_Exception
     */
    public function setFetchMode( $mode ) {
        switch ( $mode ) {
            case Zend_Db::FETCH_LAZY:
            case Zend_Db::FETCH_ASSOC:
            case Zend_Db::FETCH_NUM:
            case Zend_Db::FETCH_BOTH:
            case Zend_Db::FETCH_NAMED:
            case Zend_Db::FETCH_OBJ:
                $this->_fetchMode = $mode;
                break;
            case Zend_Db::FETCH_BOUND:
                /**
                 * @see Zend_Db_Adapter_Exception
                 */
                require_once 'Zend/Db/Adapter/Exception.php';
                throw new Zend_Db_Adapter_Exception( 'FETCH_BOUND is not supported yet' );
                break;
            default:
                /**
                 * @see Zend_Db_Adapter_Exception
                 */
                require_once 'Zend/Db/Adapter/Exception.php';
                throw new Zend_Db_Adapter_Exception( "Invalid fetch mode '$mode' specified" );
        }
    }

    /**
     * Adds an adapter-specific LIMIT clause to the SELECT statement.
     *
     * @param string $sql
     * @param int $count
     * @param int $offset OPTIONAL
     * @return string
     */
    public function limit( $sql, $count, $offset = 0 ) {
        $count = intval( $count );
        if ( $count <= 0 ) {
            /**
             * @see Zend_Db_Adapter_Exception
             */
            require_once 'Zend/Db/Adapter/Exception.php';
            throw new Zend_Db_Adapter_Exception("LIMIT argument count=$count is not valid");
        }

        $offset = intval( $offset );
        if ( $offset < 0 ) {
            /**
             * @see Zend_Db_Adapter_Exception
             */
            require_once 'Zend/Db/Adapter/Exception.php';
            throw new Zend_Db_Adapter_Exception( "LIMIT argument offset=$offset is not valid" );
        }

        $sql .= " LIMIT $count";
        if ( $offset > 0 ) {
            $sql .= " OFFSET $offset";
        }

        return $sql;
    }

    /**
     * Check if the adapter supports real SQL parameters.
     *
     * @param string $type 'positional' or 'named'
     * @return bool
     */
    public function supportsParameters( $type ) {
        switch ( $type ) {
            case 'positional':
                return true;
            case 'named':
            default:
                return false;
        }
    }

    /**
     * Retrieve server version in PHP style
     *
     *@return string
     */
    public function getServerVersion() {
        /* example: MySQL server version: 4.0.1-alpha */
        $this->_connect();
        $version = mysql_get_server_info( $this->_connection );
        $pos = strpos( $version, ':' );
        $version = substr( $version, $pos + 1, strlen( $version ) );
        return $version;
    }
}
